A. Field of the Invention
The present invention relates generally to domestic appliances, and, more particularly, to a method of forming panels which are readily assembled into domestic appliances and to panels formed by said method. While the invention is particularly suitable for and will be described in detail in connection with a demountable or knockdown chest freezer type of domestic appliance, the invention is useful in a wide variety of domestic appliances, some of which are described generally hereinafter.
B. Description of the Prior Art
Various arrangements have been heretofore proposed in the domestic appliance field to simplify the manufacture thereof and minimize the number of manufacturing operations required. For example, in the refrigeration art an attempt has been made to simplify the manufacturing process by forming a flat laminate of sheet liner and insulation, slitting the insulation along lines corresponding to the corners of the outer cabinet, folding the sheet liner at the slits and then inserting the folded laminate within the outer cabinet. Examples of such a method of manufacture are shown in U.S. Pat. Nos. 3,910,658; 3,999,820; 4,006,947; 4,033,806; 4,043,624 and 4,050,145. It has also been proposed in U.S. Pat. No. 3,834,177 to mold the entire inner liner in a complex molding apparatus.
Attempts have also been made to simplify the construction of domestic appliances by providing a wrap around type of outer cabinet, as shown for example in U.S. Pat. Nos. 4,348,068; 4,580,852; 4,082,825 and 4,632,420. While the above-enumerated arrangements have been generally suitable for their intended purpose they leave much to be desired in the simplification of the entire manufacturing process for a domestic appliance.
Various arrangements have also been heretofore proposed to provide a demountable or knockdown type of domestic appliance in which individual wall panels are shipped disassembled to a desired location and then assembled into a desired finished product, as shown, for example, in U.S. Pat. Nos. 2,127,111; 2,502,581; 2,507,379; 2,509,779; 2,521,064; 2,535,682; 3,392,497; 3,995,922 and 4,358,213. However, the panels employed in these arrangements require a complex series of manufacturing operations. Furthermore, these arrangements are complicated in construction and require the use of tools and/or separate fastening means which renders them more difficult to assemble, particularly when assembly by inexperienced field personnel or the ultimate customer is contemplated.
In addition to the above, a number of other arrangements have employed various types of interlocking joints for demountable furniture, and the like. However, these arrangements are not simple to manufacture on a mass production basis. Also, these arrangements are again quite complicated, usually require a multiplicity of small parts and separate fastening means, and are not particularly suitable for use in the domestic appliance field when assembly by the ultimate customer is contemplated. Examples of such demountable constructions are shown in U.S. Pat. Nos. 305,286; 409,893; 419,920; 582,005; 1,534,468; 2,496,184; 3,565,503; 3,674,328; 3,722,157; 4,019,298; 4,127,353 and 4,408,812.